During a geological dive northeast of Necker Island in the Hawaiian Archipelago, a NOAA ROV discovered a small cephalopod that is thought to be new to science.

The new octopus. Image courtesy of NOAA Office of Ocean Exploration and Research, Hohonu Moana 2016.

This past February, at 4,290 meters below the sea surface, the ROV Deep Discoverer came upon an incredible little octopod perched on a rock shelf. Dubbed “Casper” by an enthusiastic social media comment, this individual is peculiar among octopus species previously recorded at this depth. Before this dive, incirrate octopods, the group to which this individual belongs, were recorded at maximum depths of less than 4,000 meters. Those seen beyond this depth are cirrate octopods, like the dumbo octopuses.

These two groups are distinguished by a number of physical characteristics. The cirrate octopods have a pair of fins on their head and exhibit fingerlike protrusions from their suckers, called cirri, for which they are named. Incirrate octopods, also true their name, lack these protrusions as well as fins, and resemble shallow-water species most people are familiar with, like the common octopus (Octopus vulgaris).

Aside from being the first known cirrate octopus documented at this depth, this individual was particularly interesting because its suckers were aligned in a single row instead of two, and it lacked the pigment cells, called chromatophores, that allow octopods their famous color-changing capabilities, hence its ghostly nickname.

“It is almost certainly an undescribed species and may not belong to any described genus,” wrote NOAA’s Michael Vecchione is a news release.

Scientists estimate that the number of benthic octopus species, those living on the seafloor, reaches well into the 300s, and that many of them have yet to be formally described.